1. Field of the Invention
The present invention relates to endoscopic suturing, and more particularly to instruments for endoscopic treatment of meniscal tears.
2. Description of the Related Art
The menisci are crescent-shaped structures of fibrocartilaginous tissue located in the knee between the condyles of the tibia and the femur. The menisci, which are actually extensions of the tibia, serve to deepen the tibial plateau to better accommodate the opposing curvature of the articulating surface of the femoral condyle.
A typical injury to the knee is a meniscal tear, which can occur, for example, when the meniscus is displaced and caught between the femoral and tibial condyles during a sudden change of movement of the knee involving a combined flexion-rotation or extension-rotation motion. Meniscal tears were originally treated by removing the meniscus in an operation called a meniscectomy. However, results showed that removing the meniscus, either entirely or even partially, resulted in degenerative arthritis and instability in the knee.
As a result of the above-described complications, surgeons began treating meniscus tears with suturing techniques to retain as much of the meniscus as possible. However, suturing of a meniscal tear, like a meniscectomy, was originally an open technique, requiring a large incision and consequently longer periods of rehabilitation and recovery. Advances in instrumentation ultimately led to arthroscopic meniscal repair using long needles for passing suture through the tear.
More recently, various tacks, screws and implants have been developed for meniscal repair, which can be used arthroscopically and simplify the surgery by eliminating the need for suturing altogether. For example, U.S. Pat. No. 6,056,778, assigned to the assignee of the present application, discloses a meniscal repair device provided with a plurality of opposed crescent-shaped grooves which can be used to mend meniscal tears.
Some surgeons, however, prefer to repair meniscal tears arthroscopically using suture, but seek to avoid the difficulties associated with using long needles. Accordingly, it would be desirable to provide an instrument and method for repairing torn meniscal tissue which facilitate the passing of suture through a torn meniscus arthroscopically.